PB2448: RESTORATION OF HEMOGRAM PARAMETERS IN PATIENTS WITH HEMOBLASTOSIS AFTER TRANSPLANTATION OF AUTOLOGOUS HEMATOPOIETIC STEM CELLS
Authors: Isaeva Natalia, Natalia Zorina, Elena Poponina, Sergej Utemov, Philip Philip
Journal: HemaSphere (2023)

Topic: 22. Stem cell transplantation - Clinical Background: Autologous hematopoietic stem cell transplantation (autoHSCT) is an integral part of therapy in patients with multiple myeloma (MM), non-Hodgkin’s lymphoma (NHL) and Hodgkin’s lymphoma (HL). The timing of the restoration of hematopoiesis after autoHSCT depends, among other things, on the quantitative and qualitative characteristics of the transplant. It is known that cryopreservation of the transplant material leads to a decrease in the viability of the nucleated cells (MNC) of the transplant. Aims: To evaluate the parameters of hematopoiesis restoration in patients with MM, NHL and HL after transplantation of cryopreserved autologous hematopoietic stem cells (HSC) taking into account the characteristics of the transplant. Methods: 162 patients were examined, 118 of them - MM, 23 - NHL and 21 - HL, who received chemotherapy and autoHSCT at the KRIHBT. The age of the examined patients at the time of transplantation ranged from 20 to 67 (median - 51) years. The optimal dose of HSC was considered to be the content of CD34+ cells in thawed cell products 5x106 or more per kg of patient weight, suboptimal – less than 5x106. Percentage of viable MNC in the product was considered as an independent parameter of graft quality. The timing was determined when, after transplantation, the number of granulocytes reached 1x109/l, and the platelet content was kept at 25x109/l for three consecutive days, in addition, the number of transfused therapeutic doses of platelet concentrates (PC) and erythrocyte-containing components (ECC) was established. The data is presented in the form of a median and an interquartile interval. The Van der Waarden criterion was used for statistical analysis, and the Spearman correlation coefficient was used to assess the relationship between the features. Results: Among all patients, 52.5% received the optimal dose of HSC, and 47.5% of patients received the suboptimal dose (less than 5x106/kg). In patients with NHL, when transplanting a suboptimal dose of HSC (n=16), the platelet recovery period was significantly longer than in patients (n=7) when transplanting the optimal dose (19.0 days (14.5; 27.5) vs 14.5 days (9.8; 20.8), p = 0.024). No such differences were found in patients with MM and HL. The need for PC and ECC transfusions in the observed groups of patients coincided. The viability of MNC in the transplant product in 51.8% of cases was more than 75%, in 48.2% - did not exceed 75%. In the general group of patients with the viability of MNC at levels “>75%” and “<75%”, the recovery time of the number of granulocytes (13.1 days (12.2; 14.3) vs 13.2 days (12.0; 14.1), p = 0.12) and platelets (15.5 days (13.1; 20.2) vs 14.0 days (12.2; 20.8), p = 0.08) were comparable, differences in the number of PC and ECC transfusions were also not revealed. Correlation analysis revealed that in patients with MM and HL there was no association between the restoration of hematopoiesis parameters and the viability of MNC in the transplant product, and in patients with NHL, an inverse relationship (r = - 0.34, p = 0.01) was established between the duration of granulocyte recovery and the viability of MNC. Summary/Conclusion: In patients with NHL, the duration of platelet recovery is 1,3 times longer when using a suboptimal dose of HSC than the optimal one, whereas in patients with HL and MM, the period of cytopenia does not increase during transplantation of a suboptimal dose of HSC. In NHL, the lengthening of the period of granulocytopenia is associated with a decrease in the viability of MNC in a cryopreserved transplant. Keywords: Multiple myeloma, Hodgkin’s disease, Autologous bone marrow transplant, Non-Hodgkin’s lymphoma